|
The following Periodic Check Tests on each brand of electrodes
shall be carried out:-
(a) Periodic check tests consist of a selection of the tests
prescribed under Regulations
95 and 97
and they shall be repeated at intervals of not more than 6
months to provide evidence that the electrodes currently produced
continue to possess the properties recorded in the initial
tests.
(1) All-weld tensile test with any two sizes of electrodes
within the limits prescribed in clause (a) of
Regulation 95.
(2) One Tee joint fillet weld hot cracking test as prescribed
in clause (b) of Regulation
95.
(b) For deep penetration butt-welding electrodes, one transverse
tensile test specimen and two transverse bend test specimens
shall be prepared and tested as prescribed in Regulation
96 and the specimens shall show that a complete penetration
has been achieved.
(c) For deep penetration fillet welding electrodes one cruciform
fillet weld tensile test shall be taken as prescribed in Regulation
97(1) and the two outer discards from the test pieces
shall show a minimum penetration beyond the root as required
under Regulation 97(2).
APPENDIX H-1 (See Regulation 95)
(1) Parent Metal for Test Plates.- The parent metal
used in preparing test pieces and test specimens shall be
mild steel of welding quality in the normalized condition
(this condition is optional in the case of all-weld metal
tests) with an ultimate tensile stress of not less than 28
and not more than 32 tons per square inch and an elongation
of not less than 20 per cent on standard test piece A(1) (Appendix
B).
(2) All-Weld Metal Test.- Method of preparation of
test pieces. The temperature of the parent metal shall be
between 50° and 100°F (10° - 38°C) immediately
before depositing the first run of weld metal. The test specimen
shall not be subjected to any mechanical or thermal treatment
other than that required herein. All-weld test pieces shall
be prepared as shown in Figure 1* by depositing weld metal
between the chamfered edges of two plates, each 7/8 inch thick.
The preparation of the plates shall give an included angle
of 20° and the distance between the plates at the root
edges shall be ½ inch to 17/32 inch. The joint shall
be closed at the bottom by a backing pipe 1¼ inch wide
by ¼ inch thick. The two plates shall be 7 inches long
and the dimension B from square edge to root edge of each
side plate shall be between:
2 inches minimum and 3 inches maximum when testing 12 S.W.G.
(3/32) inch electrodes.
*As shown in this Appendix.
3 inches minimum and 4 inches maximum when testing 10 S.W.G.
or 8 S.W.G. electrodes.
4 inches minimum and 5 inches maximum when testing 6 S.W.G.
electrodes.
5 inches minimum and 6 inches maximum when testing ¼
inch or 5/16 inch electrodes.
The assembly shall be welded together with these plates
pre-set so that the gap at the top between the chamfered edges
of the plates is 1 inch and the plates may be approximately
level when the butt-weld is completed.
The weld metal shall be deposited in single or multi-run
layers and the direction of deposition of each layer shall
be alternatively from each end of the specimen. Each run of
weld metal shall not be less than 1/16 inch and not more than
1/8 inch thick. The time interval between the completion of
one run and the commencement of deposition of the succeeding
run shall be not less than 5 minutes. The assembly shall not
be quenched between the deposition of individual runs. The
welding current used shall be within the appropriate range
given by the manufacturer. The welding position for the assembly
shall be flat, unless this is contrary to the recommended
position for the electrode, in which case the position of
weld shall be as recommended by the manufacturer.
On completion of the weld the specimen shall be allowed
to cool in still air. The portion including the weld shall
then be removed by cutting away the excess plate at the places
indicated in Figure 1.
The all-weld test piece shall be heat-treated by raising
to a uniform temperature of 1112° to 1202°F (600°
to 650°C) and maintained at that temperature for one hour
and then allowed to cool slowly outside the furnace, protected
from draughts and chilling. A tensile test specimen shall
be machined from the test piece to the dimensions given in
Figure 1(a)* taking care that the longitudinal axis of the
specimen coincides with the centre line of the weld and the
mid-thickness of the plate as indicated in Figure 1. The specimen
then shall be tested for tensile strength.
(3) Impact Test Specimen.- The Izod impact test specimens
shall be machined from the weld metal test pieces to the dimensions
given in Figure 2,* care being taken that the longitudinal
axis of the test piece coincides with the centre line of the
weld and mid-thickness of the plate. The temperature of the
test specimen at the time of testing shall not be less than
50°F (10°C).
(4) Hot Cracking Test.- A 6 inches x 4 inches x ½
inch plate shall be welded to a second plate 6 inches x 6
inches x ½ inch in the form of a close square Tee joint
as shown in Figure 3*. The edge of the first plate abutting
the surface of the second shall be prepared by machining or
grinding. The gaps between parts after tack welding at the
ends shall not exceed 0.01 inch.
_________________________________________________*As shown
in this Appendix.
Two fillet welds 5 inches long and ¼ inch in leg
length shall be deposited in the flat position with a single
6 S.W.G. (or 0.2 inch) electrode, using the maximum current
of the range recommended by the manufacturer. The test piece
shall be so positioned that the slope and the rotation of
the weld are zero. The second weld shall be started at that
end where the first run was finished after time interval of
4 to 5 seconds. The slag shall be removed after the test piece
is cooled in still air to the room temperature. The surfaces
of the weld shall be visually examined for cracks.
The second plate shall be slit and the welds broken open
as shown in Figure 4*. The weld shall not show any evidence
of hot cracking as indicated by oxidation or temper colouring
of the surface of the fractures.
(5) Transverse Tensile and Bend Tests.- The transverse
tensile and bend test pieces shall be made as shown in Figure
5* by butt-welding together two ½ inch plates of suitable
length and not less than 6 inches in width. The Plate edges
shall be prepared to form a single Vee joint the details of
which shall be as follows:-
(See Figure 5a)*
Angle between fusion faces 60° - 70°.
Root face 1/8 inch.
Maximum gap 1/8 inch.
The plate edges shall be prepared as per Figure 5(a)*, and
pre-set to allow for slight distortion after welding.
The welding procedure in making out the test pieces shall
be according to the position of welding as in Table 1 below:-______________________________________________________*As
shown in this Appendix.
TABLE 1
Welding procedure for preparation of transverse tensile
test and bend test pieces
Welding position for test pieces (all angles±5°)
as shown in Table-5 below
|
Welding Procedure
|
FLAT
Weld slope 0°
Weld rotation 180°
|
1. All runs made with 8 S.W.G. electrodes.
2. First run 6 S.W.G. electrodes. Subsequent
runs 5/16 inch diameter electrodes (or largest
size manufactured).
|
INCLINED
Weld slope 30°
Weld rotation 45
|
Weld slope 30°
Weld rotation 45
First run 8 S.W.G. electrodes. Subsequent runs
6 S.W.G. electrodes.
|
HORIZONTAL-VERTICAL
Weld slope 0°
Weld rotation 90°
|
First run 8 S.W.G. electrodes. Subsequent
runs 6 S.W.G. electrodes. |
VERTICAL
Weld slope 90° |
All runs made with 8 S.W.G. electrodes.
|
OVER HEAD
Weld slope 0°
Weld rotation 180° |
All runs made with 8 S.W.G. electrodes.
|
In all cases a backing run shall be made with 8 S.W.G. electrodes
in the welding position applicable to the test piece, after
cutting out a groove of 1/8 inch deep if considered necessary,
as in Figure 5(a)*.
The test pieces for the inclined and vertical positions
shall be welded using the upwards method unless
the electrodes manufacturer specifically recommends that only
the downwards method shall be used. If both methods
are recommended, test pieces welded by each method shall be
made.
After welding, the test pieces shall be cut by sawing on
machine to form one transverse tensile, one face-bend and
one root-bend test specimen, as indicated in Figure 5*.
(6) Transverse Tensile Test.- Transverse tensile test specimens
shall conform to the dimensions given in Figure 6*. The upper
and lower surfaces of the weld shall be filed, ground or machined
level with the respective original surfaces of the plates.
Where the surfaces of the plates are not level with each other
the metal may be cut away to bring them approximately level,
provided that the thickness of the plate is not reduced by
more than a total of 0.04 inch.
_________________________________________________*As shown
in this Appendix.
The test specimens shall then be tested for tensile test
as in Appendix-B.
(7) Transverse Bend Test.- The bend test specimens
shall be 1½ inches in width. The upper and lower surfaces
of the weld shall be filed, ground or machined level with
the respective original surfaces of the plates, with the proviso
as in item (6) above. Tool marks should be avoided as they
lead to location of stress and may cause premature failure.
For this reason the direction of machining of the surfaces
should be along the specimens and transverse to the weld.
The sharp corners of test specimens shall be rounded to a
radius not exceeding 1/20 inch.
The test specimens shall be bent through an angle of 180°
over former having a diameter equal to three times the thickness
of the specimen, as shown in Figure 7*. One test specimen
shall be tested with the face of the weld in tension and one
with the root of the weld in tension.
(8) Cruciform Fillet Weld Tensile Test - Normal Penetration
Electrodes.- The specimens shall be prepared as shown in Figure
8*. Care shall be taken that the centre lines of two vertical
plates are in the same plane. The parent metal used shall
be at a temperature between 50° - 100°F (10° -
38°C) immediately before depositing the first run of weld
metal. The test specimens shall not be subjected to any mechanical
or thermal treatment, other than what is given in this appendix.
The plates shall be so placed that each weld shall be deposited
in the appropriate welding position, using the procedure specified
in Table 2 below:-
TABLE 2
Welding procedures for preparation of Cruciform fillet weld
tensile test pieces for normal penetration electrodes
Welding position for test pieces (All angles
±5°) as shown in Table 5 below.
|
Welding Procedure
|
FLAT
Weld slope 0°
Weld rotation 0°
|
One run 4 S.W.G. or 5/16 inches diameter
electrodes. |
INCLINED
Weld slope 30°
Weld rotation 90° |
Not more than 3 runs 8
S.W.G. electrodes. |
HORIZONTAL VERTICAL
Weld slope 0°
Weld rotation 45°
|
FNot more than 3 runs
6 S.W.G. or 4 S.W.G. electrodes.
|
| Vertical Weld slope 90° |
One run 8 S.W.G. electrodes. |
OVERHEAD
Weld slope 0°
Weld rotation 180° |
Not more than 3 runs 8
or 6 S.W.G. electrodes. |
______________________________________________________________
*As shown in this Appendix.
The welding current used shall be as per recommendation of
the manufacturer.
The test pieces for the inclined and vertical positions
shall be welded using upwards method, unless the
manufacturer specifically recommends down-wards
method. If both methods are recommended, test pieces welded
by each method shall be made. The completed test piece shall
be cut into strips by sawing or machining as shown in Figure
8* and the inner strip tested in tension as indicated therein.
__________________________________________________*As shown
in this Appendix.
APPENDIX H-2
(See Regulation 96)
Butt-Weld Tests.- Deep Penetration Electrodes.
The parent metal shall be at a temperature between 50°
and 100°F (10° - 38°C) immediately before depositing
the first run of weld metal and the test specimen shall not
be subjected to any mechanical or thermal treatment other
than that specified in this Appendix. The test pieces shall
be made by welding together two plates not less than 6 inches
wide and of the thickness specified in Table 3 below:
TABLE 3
Welding procedure for preparation of butt-weld test Pieces
Deep Penetration Electrodes
Welding position for test pieces (All angles
+5°) as shown in Table 5 below
|
Welding Procedure
|
| FLAT
Weld slope 0°
Weld rotation 0°
|
1. One run on each side of joint with the
largest size of electrode manufactured. Plate thickness
equal to twice diameter of the core wire or ½ inch
(whichever is less).
2. One run on each side of joint with the smallest
size of electrode manufactured (but not less than 1/8
inch diameter). Plate thickness equal to at least twice
diameter of the core wire.
3. One run on each side of joint with ¼ inch
diameter electrodes. Plate thickness not less than ½
inch.
|
The length of the plates shall be sufficient to accommodate
on one side the run length of a complete electrode, but in
any case shall not be less than 10 inches.
The joint edges of the plates shall be square cut and any
gap between the plates after tack welding at the ends shall
not exceed 0.010 inch.
The welding procedure shall be as set out in the above table
and in addition the first electrode used for welding each
side shall be consumed for its full length except for a stub
end of not more than 2 inches. The welding current used shall
be as recommended by the manufacturer and each weld shall
be deposited in the flat welding position and started as shown
in Figure-9.*
*As shown in this Appendix.
Each test piece shall be so marked that the side first welded
remains identifiable after the test specimens have been cut
out, as shown in Figure- 9*. The specimens shall be cut out
by sawing or machining to provide one tensile test specimen
and two transverse bend test specimens. The two outer discards
shall be retained and their inner edges shall be prepared
and etched to reveal weld metal one as required for the butt-weld
penetration test.
(1) Transverse Tensile Test.- Transverse tensile test
specimen shall conform to the dimensions given in Figure 6y
for such specimens and where the surfaces of the plates are
not, level they shall be made so by machining or filling provided
the thickness of the plate is not reduced by more than a total
of 0.04 inch. The specimen shall then be tested for tensile
test.
(2) Transverse Bend Test.- Each transverse bend test
specimen shall be of a width equal to three times its thickness.
The upper and lower surface of the weld shall be filed, ground
or machined level with the respective original surface of
the plates provided the thickness of the plates is not reduced
by more than a total of 0.04 inch. The direction of machining
of the surfaces shall be along the specimen and transverse
to the weld. Tool marks shall be avoided to eliminate premature
failure, and the sharp corners rounded to a radius not exceeding
one-tenth the thickness of the specimen. The test specimen
shall be bent through an angle of 180° over a former having
a diameter equal to three times the thickness of the specimen
as shown in Figure 10*. One test specimen shall be tested
with the side first welded in tension, and one with the other
side in tension.
(3) Cruciform Fillet Weld Test - Deep Penetration Electrodes.-
The parent metal shall be at a temperature between 50°
and 100°F (10° - 38°C) immediately before depositing
the first run of weld metal. The test specimen shall not be
subjected to any mechanical or thermal treatment other than
that specified in this Appendix.
For each test piece, two pieces of plate, of sufficient
length to suit the testing machine shall be welded to a third
plate by means of fillet welds as shown in Figure 11*. Care
shall be taken that the centre lines of the vertical plates
are in the same plane. The width of the plates shall be sufficient
to accommodate on one side the run length of complete electrode,
but in any case shall be not less than 10 inches. The thickness
of each piece of plate shall be as specified in Table 4 below.
The edge of each vertical plate abutting the surface of
the horizontal plate shall be square cut prepared by machining,
grinding or gas cutting), and any gap between the horizontal
plate and the vertical plates, after tack welding at the ends
in preparation for welding shall not exceed 0.01 inch.
* As shown in Appendix.
Y As shown in Appendix H-1.
The welding procedure followed in making the test pieces
shall be as set out in Table 4 below with the addition that
the first electrode used for welding each fillet shall be
consumed for its full length except for a stub end of not
more than 2 inches.
TABLE 4
Welding procedure for preparation of cruciform fillet weld
test pieces (deep penetration electrodes)
Welding position for test pieces
(as shown in table 5 below) all angle ±5°
|
Welding Procedure
|
|
HORIZONTAL VERTICAL
Weld slope 0°
Weld rotation 45°
|
1. One run on each side of each joint with the largest
size of electrode manufactured. Plate thickness equal
to at least twice diameter of the core wire or ½
inch (whichever is less). Maximum fillet leg length
shall be 1/8 inch less than the plate thickness.
2. One run on each side of each joint with the smallest
size of electrode manufactured (but not less than ½
inch diameter), Plate thickness equal to at least twice
diameter of the core wire. Maximum fillet leg length
shall be 1/8 inch less than the plate thickness.
3. One run of each side joint with1/4 inch diameter
electrodes. Plate thickness not less than1/2 inch and
fillet leg length not to exceed 3/8 inch.
|
The welding current used shall be within the appropriate range
recommended by the manufacturer and each weld shall be deposited
in the horizontal-vertical position.
The order of laying down fillets shall be as indicated by
the numbers 1, 2, and 4 in Figure 11*. The adjacent fillet
shall be laid in opposite directions. After welding the test
piece shall be cut by sawing or machining as indicated in
Figure 11* and the inner edges of the two outer discards shall
be prepared and etched as specified for the cruciform fillet
weld tensile tests for normal penetration electrodes in Appendix
H-1.
The test specimen shall then be tested for tensile test.
*As shown in this Appendix.
WELDING POSITIONS ARE DEFINED AS FOLLOWS:
POSITIONS
|
SLOPE
|
ROTATION
|
SYMBOL
|
ILLUSTRATION
|
FLAT
|
NOT EXCEED-ING 10°
|
NOT EXCEED-ING 10°
|
F
|
FIG.4
|
INCLINED
|
EXCEED-ING 10° NOT
EXCEED-ING 45°
|
NOT EXCEED-ING 90°
|
I
|
FIG.5
|
HORIZON-TAL VERTICAL
|
NOT EXCEED-ING 10°
|
EXCEED-ING 10° NOT EXCEED-ING
90°
|
H
|
FIG.6
|
VERTICAL
|
EXCEED-ING 45°
|
ANY
|
V
|
FIG.7
|
OVERHEAD
|
NOT EXCEED-ING 45°
|
EXCEED-ING 90°
|
O
|
FIG.8
|
NOTE: THE FIVE POSITIONS DEFINED ABOVE COVER ANY POSSIBLE COMBINATION
OF SLOPE AND ROTATION SO THAT EVERY WELD CAN BE CLASSIFIED IN
ONE OF THESE POSITIONS.
|